Foliated conglomerate clasts do not much resemble the
Paleozoic metamorphic rocks, but instead resemble the footwall
phyllites.In 2005, mapping in
the Upper Gallagher area suggested that the conglomerate clasts were derived
from footwall phyllites and that the phyllites were foliated versions of
mafic volcanics and intrusives that had been dated as late Triassic.Something is very wrong with the old
model.It's logic demands that
the ore contact be located on a Triassic-Paleozoic unconformity.This is inconsistent with radiometric
dating, it is inconsistent with expected VMS deposit morphology, and it
doesn't reflect the widely varying morphology and lithology of the
conglomerates.A
penecontemporaneous origin for S1 would solve these problems, in essence,
making S1 and S2 the same foliation caused by the same event.More understanding of the formation
of the conglomerate is necessary to complete this picture, but that will be
for later.

S2 Pressure Solution Bedding Plane foliation

Isoclinal folding from regional metamorphism, possibly
Cretaceous

Diagenetic foliation enhanced by a shear stress during
diagenesis and induration.

Early bedding plane foliations are quite common throughout
the world.Historically these
were attributed to regional scale isoclinal folding even though evidence for
the folds was often absent or ambiguous.The prevalence of the fabric and the unlikelihood of the
vertical stress regime postulated to create bedding plane fabric has caused
some to rethink the origin of these foliations.More recent work, such as that of Passchier and Trouw, has
attributed such fabrics to diagenesis.At least in part the change in thought has come with the recognition
that foliation may be created or enhanced by pressure solution-a process that
is not dependent on high pressure and temperature to operate.

S3 Pressure Solution Spaced Cleavage and crenulation

A result of a third regional metamorphic event-this one is
speculated to be Cretaceous as well

Progressive deformation from diagenetic event.Increased lithification results in
different fabric.

The occurrence of spaced cleavage and crenulation at high
angles to bedding plane foliation is a common occurrence world-wide-perhaps
too common.Again, the
recognition of crenulation and spaced cleavage as being a product of pressure
solution (not necessarily a high P-T process) has opened the possibility of
new interpretations.Pressure
solution formation of a bedding plane cleavage in a diagenetic environment
has some distinct implications for formation of secondary fabrics such as
S3.Because pressure solution
can result in significant volume loss, and that volume loss is plainly
evident at Greens Creek, one would expect a progressive deformation.I.e., as the rocks lose volume, they
move and deform to accommodate that loss.The nature of the secondary deformation will be different
from the first for a couple of reasons.First, the change in the rock brought about by pressure solution
bedding plane foliation will change the rock.And, second, progressive lithification of the rock will
change the nature of the deformation.

F2 folding

Folds and inhomogeneous folds in the ore zone approach
isoclinal.Larger F2, such as
the LSW-200S fold are open.

Ore zone folds that appear isoclinal or inhomogeneous are
soft sediment deformation.The
larger fold is part of the same sequence of progressive collapse.

The established folding scheme at Greens Creek is not
understandable to me-and I expect that it is not really understandable to
anyone else either.It has been
a matter of debate among structural consultants as well as others.That doesn't mean that a fold can't
be traced from one place to another.Some of them can and that can be useful.In fact, the most prominent feature of the deposit when
looking at Datamine views is a very large open fold with approximate right
angle limbs that runs from the Northwest ore bodies through the Lower
Southwest ore body to the 200S ore body.This fold appears to me to be an F3 fold in the
established scheme, but it has been called an F2 by some.Tight folds labeled F2 occur in the
ore zone and in the argillite beds immediately overlying the ore.Attempts to trace these over long
distances have mostly failed and "inhomogeneity" has been offered as an
"explanation."(But of course
that isn't an explanation at all. )The increased intensity of the folding in the ore zone has more or
less been ignored.There has
been some discussion of the effects of the orebodies in localizing
structure-variously they are described as competent rocks that affect the
locations of folds, or incompetent rocks that flow into the noses of
folds.Shearing, healed shears,
duplexing, and other disconformities associated with all stages of folding
have been either ignored or glossed over.Despite this, they are among the most prominent structural
features ones sees in the ore zones.They don't fit the established scheme.

The new model presents a different way of looking at the
folding which has the power to explain and simplify all of the features
without the logical conflicts and contradictions.When one views the tight folds in the ore zone as soft
sediment features related to progressive deformation accompanying seafloor
collapse, all of the features fall into place.The stratigraphic control of deformation makes sense, the
coincidence of folding and orebodies makes sense-they are both related to the
deep structure forming the collapse.Disconformities are explained.Traceability is much more understandable.

F3 folding

Open folds in the footwall resulting from second phase of
Cretaceous tectonism.

These are part of progressive deformation

Much of the discussion of F3 folds is linked to the above discussion
of F2 folds.As noted above,
there are some serious problems distinguishing between the two.In all likelihood, an F3 fold is one
that has been folded or appears to fold the S2 foliation.Again, progressive deformation is a
much simpler explanation.

F4 folding

Coaxial with F3 and may be progressive from F3

Rotated F3 folds.

The work I have seen defining F4 folds shows that these
are separated from F3 folds by disconformities.In all probability, these are just earlier folds rotated in
a progressive deformation.They
are coaxial and look very much the same as folds described as F3.

Folding summary

4 or more phases.

One phase of progressive deformation,

The standard model has become so complicated that it now seems
all but impossible.The model's
four phases are recognized as being inadequate, so more phases have been
added.I am not sure what we are
up to now, but it is at least six or more.This is all in rocks that as one can see from the picture
of pillow basalt at Gambier Bay have no particular regional deformation at
all.The Occam's Razor for this
problem is one progressive deformation from a localized seafloor collapse.Suddenly the problem is simple.

Unfoliated areas that have sharp crosscutting relationship
with foliated rocks.

No formal explanation given in any reports.Has been logged as "carbonate
alteration."

These are clastic dikes.

When one looks at Greens Creek core day after day, one
sees some very strange stuff.One of the things I saw were areas where the phyllitic fabric
disappeared.Completely
unfoliated rock cross-cut the foliation--it was as if concrete had been
poured into cracks in the rock.There are other non-conforming and apparently unmetamorphosed rocks in
and near the ore zones too.I
saw a cross cutting sulfide carbonate breccia in the 200S zone.To some extent-and in some places,
the conglomerates themselves have these characteristics.The easy explanation is that they are
clastic dikes.But the reality
is that they have been ignored because they do not fit the standard model.

Separation of sulfide and carbonate ores as noted by Katja
Freitag

Two vents separated in time.(per Freitag)

Soft sediment deformation has moved sulfide off of
carbonate ores.

The PhD student, Katja Freitag, did a structural analysis
of the Lower Southwest orebody and concluded that it consisted of two mounds
of ore-one sulfide and one carbonate.Her conjecture on the reason for this was that there were two vents
operating at two different times to build the two mounds.The reasoning was that one vent
became plugged and the other active.A simpler explanation is that movement after deposition separated the
carbonate and sulfide masses.They would have been very different consistencies in the time shortly
after deposition.The absence of
any feeders is best explained by pressure solution in the footwall.And the out of place bits of sulfide
are remnants of the larger moved mass.

Apparent different degrees of deformation in sulfides than
surrounding rock.

Sulfides are less susceptible to high P-T metamorphism
than surrounding rock.

Surrounding rocks are deformed by pressure solution
processes and sulfides are less soluble.

There is little question that the rocks have been subject
to an intense pressure solution deformation.The microscopic textures seem indicative.Understanding of low grade
metamorphism of sulfide minerals is in a sorry state to say the least.From what I can tell, deformation of
sulfide beds is considered to be evidence of metamorphic deformation, just
because.Other sorts of
deformation don't fit the models.On a macroscopic level, Greens Creek ores appear to have flowed in
places.In some areas, things
that look like bedding in the ores look like flow banding when one steps
back.

Sulfides appear to be concentrated in fold hinges

Sulfides flow more easily in metamorphic situations than
surrounding rock.

Fold hinges represent conduits for fluids and centers of
mounds.Slumping and soft sediment
deformation have moved sulfides to hinge locations, partly by duplexing.

Sulfide minerals are among the most brittle of minerals at
lower temperatures.They are
also extremely resistant to pressure solution, an important observed process
at Greens Creek.In polished
section, Greens Creek MFB shows textures that are most easily explained by
movement of sulfide muds.Pyrite
crystals have rounded corners and some are even round in shape.Some crystals that appear as squares
with rounded corners have centers that appear to be ghosts of framboids.Where sulfides constitute a smaller
proportion of the rock or in inclusions in the massive sulfides, pyrite takes
the form of unrecrystallized framboids.The simplest way to explain the form and texture of the ore is
deformation of semi-lithified sulfide muds.

Origin of ladder veins in MA

I think they are attributed to D2 extension prior to D2
contraction.Freitag attributed
them to diagenesis based on petrographic study.

Ladder veins represent extension in shallow levels of a
collapse.(And they would be
diagenetic or at the time of diagenesis.)

One report described the ladder veins as the result of a
100 percent extension of the rock as the first part of a progressive,
presumably Cretaceous, deformation that eventually had a several hundred
percent contraction.On the
other hand, Freitag attributed them to diagenesis.This is quite a variety of opinions.Some better study is needed for
something that is such an important guide to ore.Ladder veins have been observed in progressive
penecontemporaneous deformation elsewhere and that seems to be the easiest
explanation here.